﻿OF 
  TERRESTRIAL 
  MAGNETISM 
  AT 
  SEVERAL 
  PLACES, 
  ETC. 
  439 
  

  

  TABLE 
  No. 
  II. 
  

  

  

  

  

  Observations 
  for 
  the 
  Correction 
  for 
  

  

  Temperature 
  of 
  Needle 
  A. 
  

  

  

  > 
  

   o 
  

  

  Times 
  of 
  Beginning 
  

  

  rature 
  

   inning 
  

   End. 
  

  

  v. 
  

  

  o 
  . 
  

  

  CO 
  

  

  o 
  

  

  1 
  s 
  

  

  S3 
  

  

  fc" 
  1 
  a 
  

  

  «H-J3 
  

  

  Mean 
  Tempe- 
  

   rature 
  of 
  each 
  

   set 
  of 
  Observ- 
  

   ations. 
  

  

  Time 
  

   Vibra- 
  

   n 
  each 
  

   t. 
  

  

  

  O.I 
  

   o 
  

  

  6 
  

   JZi 
  

  

  and 
  Ending. 
  

  

  Tempe 
  

  

  at 
  Beg 
  

  

  and 
  

  

  

  °.2 
  

   So 
  

  

  .S 
  a. 
  

  

  

  Mean 
  

   of 
  Ten 
  

   tions 
  i 
  

  

  se 
  

  

  Observers. 
  

  

  Hours. 
  

  

  Mins. 
  

  

  Sees. 
  

  

  Fah.° 
  

  

  Inch. 
  

  

  Fah.° 
  

  

  Sees. 
  

  

  Fah.° 
  

  

  Seconds. 
  

  

  

  P.M. 
  

  

  4 
  

  

  14 
  

  

  26.4 
  

  

  72 
  

  

  

  

  

  

  

  

  October 
  5th, 
  

  

  

  

  66 
  

  

  32 
  

   34 
  

  

  27.8 
  

   30.8 
  

  

  72 
  

  

  3 
  

  

  300* 
  

  

  72.0 
  

  

  36.05 
  

  

  

  

  1835. 
  

   Bache 
  and 
  

  

  1. 
  

  

  

  

  52 
  

  

  32.0 
  

  

  701 
  

  

  4 
  

  

  300t 
  

  

  71.2 
  

  

  36.04 
  

  

  71.6 
  

  

  36.045 
  

  

  Courtenay. 
  

  

  

  P.M. 
  

  

  6 
  

  

  31 
  

  

  57.2 
  

  

  36 
  

  

  

  

  

  

  

  

  

  

  

  

  46 
  

  

  55.2 
  

  

  32 
  

  

  4t 
  

  

  250 
  

  

  33.7 
  

  

  35.92 
  

  

  

  

  

  

  

  6 
  

  

  59 
  

  

  07.6 
  

  

  32 
  

  

  

  

  

  

  

  

  Bache 
  and 
  

  

  2. 
  

  

  

  7 
  

  

  17 
  

  

  04.0 
  

  

  36 
  

  

  n 
  

  

  300 
  

  

  33.7 
  

  

  35.88 
  

  

  33.7 
  

  

  35.900 
  

  

  Courtenay. 
  

  

  

  P.M. 
  

  

  8 
  

  

  42 
  

  

  23.2 
  

  

  61 
  

  

  

  

  

  

  

  

  

  

  

  9 
  

  

  00 
  

  

  23.6 
  

  

  62 
  

  

  3£ 
  

  

  300 
  

  

  61.7 
  

  

  36.01 
  

  

  

  

  

  

  

  9 
  

  

  02 
  

  

  55.2 
  

  

  62 
  

  

  

  

  

  

  

  

  Bache 
  and 
  

  

  3. 
  

  

  

  

  20 
  

  

  56.2 
  

  

  64 
  

  

  4 
  

  

  300 
  

  

  62.9 
  

  

  36.03 
  

  

  62.3 
  

  

  36.020 
  

  

  Courtenay. 
  

  

  

  P.M. 
  

  

  10 
  

  

  29 
  

  

  24.4 
  

  

  92 
  

  

  

  

  

  

  

  

  

  

  

  

  44 
  

  

  28.0 
  

  

  90 
  

  

  M 
  

  

  250 
  

  

  91.2 
  

  

  36.14 
  

  

  

  

  

  

  

  11 
  

  

  10 
  

  

  33.2 
  

  

  86 
  

  

  

  

  

  

  

  

  1 
  4. 
  

  

  

  28 
  

  

  38.2 
  

  

  91 
  

  

  3 
  

  

  300 
  

  

  88. 
  5| 
  36.17 
  

  

  89.8 
  

  

  36.155 
  

  

  Bache. 
  

  

  The 
  second 
  set 
  of 
  observations 
  was 
  introduced 
  to 
  ascertain 
  the 
  al- 
  

   lowance 
  to 
  be 
  made 
  for 
  the 
  diurnal 
  variation 
  of 
  intensity. 
  Reducing 
  

   it 
  to 
  the 
  temperature 
  of 
  the 
  first 
  set 
  by 
  using 
  the 
  mean 
  coefficient 
  

   from 
  the 
  entire 
  series, 
  it 
  shows 
  an 
  increase 
  in 
  the 
  time 
  of 
  ten 
  oscilla- 
  

   tions 
  between 
  4 
  and 
  5 
  P. 
  M., 
  the 
  mean 
  hour 
  of 
  making 
  the 
  first 
  set, 
  

   and 
  9 
  P. 
  M., 
  the 
  mean 
  hour 
  of 
  the 
  third, 
  of 
  .022 
  seconds. 
  Apply- 
  

   ing 
  the 
  proportional 
  part 
  of 
  this 
  correction 
  to 
  the 
  sets 
  numbered 
  2 
  and 
  

   4, 
  the 
  temperatures 
  and 
  times 
  will 
  be 
  found 
  to 
  be 
  as 
  follows, 
  

   No. 
  1, 
  71.6o, 
  36.045 
  seconds. 
  

  

  2, 
  33.7°, 
  35.888 
  « 
  

  

  4, 
  89.8°, 
  36.124 
  « 
  

   And 
  the 
  corrections 
  deduced 
  from 
  a 
  comparison 
  of 
  the 
  several 
  sets 
  

   will 
  be 
  more 
  accordant, 
  than 
  when 
  the 
  daily 
  variation 
  is 
  not 
  consi- 
  

   dered. 
  The 
  values 
  of 
  the 
  coefficient 
  are, 
  

  

  * 
  Terminated 
  in 
  an 
  arc 
  rather 
  greater 
  than 
  two 
  degrees, 
  

   t 
  Terminated 
  in 
  an 
  arc 
  rather 
  less 
  than 
  two 
  degrees. 
  

   % 
  Above 
  four 
  inches. 
  

  

  VOL. 
  V. 
  — 
  5 
  N 
  

  

  